vv ISSN: 2641-3116 DOI: https://dx.doi.org/10.17352/ojor CLINICAL GROUP Received: 31 March, 2021 Research Article Accepted: 07 April, 2021 Published: 10 April, 2021 *Corresponding author: Dr. Kartik Sonawane, Uncovering secrets of the Junior Consultant, Department of Anesthesiol- ogy, Ganga Medical Centre & Hospitals, Pvt. Ltd. Coimbatore, Tamil Nadu, India, E-mail: beauty bone: A comprehensive Keywords: Clavicle fractures; Floating shoulder sur- gery; Clavicle surgery; Clavicle anesthesia; Procedure review of anatomy and specific anesthesia; Clavicular block regional anesthesia techniques https://www.peertechzpublications.com of clavicle surgeries Kartik Sonawane1*, Hrudini Dixit2, J.Balavenkatasubramanian3 and Palanichamy Gurumoorthi4 1Junior Consultant, Department of Anesthesiology, Ganga Medical Centre & Hospitals, Pvt. Ltd., Coimbatore, Tamil Nadu, India 2Fellow in Regional Anesthesia, Department of Anesthesiology, Ganga Medical Centre & Hospitals, Pvt. Ltd., Coimbatore, Tamil Nadu, India 3Senior Consultant, Department of Anesthesiology, Ganga Medical Centre & Hospitals, Pvt. Ltd., Coimbatore, Tamil Nadu, India 4Consultant, Department of Anesthesiology, Ganga Medical Centre & Hospitals, Pvt. Ltd., Coimbatore, Tamil Nadu, India Abstract The clavicle is the most frequently fractured bone in humans. General anesthesia with or without Regional Anesthesia (RA) is most frequently used for clavicle surgeries due to its complex innervation. Many RA techniques, alone or in combination, have been used for clavicle surgeries. These include interscalene block, cervical plexus (superficial and deep) blocks, SCUT (supraclavicular nerve + selective upper trunk) block, and pectoral nerve blocks (PEC I and PEC II). The clavipectoral fascial plane block is also a safe and simple option and replaces most other RA techniques due to its lack of side effects like phrenic nerve palsy or motor block of the upper limb. We present a comprehensive review of anatomy and RA techniques of clavicle surgeries. This review will help readers understand the functional anatomy and nature of clavicle fractures, and apply an algorithmic approach to procedure-specific blocks for complexly innervated structures like clavicle. Abbreviations which means “little key” because it rotates along its axis like a key when the shoulder is abducted. Fractures of the clavicle are GA: General Anesthesia; RA: Regional Anesthesia/Analgesia; relatively common, accounting for up to 10% of all fractures SCUT block: Supraclavicular + Upper Trunk block; PEC: Pectoral [1]. Clavicle surgeries can be done under Regional Anesthesia Nerve block; ISB: Interscalene Block; CPB: Clavipectoral (RA) with or without general anesthesia (GA), depending on the Fascial Plane Block; SCN: Supraclavicular Nerve; AC joint: fracture site. Analgesia for clavicle fractures can be challenging Acromioclavicular joint; SIA: Single-Injection Approach; DIA: for anesthesiologists due to the complex and varied innervation Double-Injection Approach; TIA: Triple-Injection Approach in this region. Introduction Many RA techniques, either individually or in combinations, have been used for perioperative analgesia for clavicle surgeries. The name ‘clavicle’ is derived from the Latin word Clavicula, Some of these techniques include Interscalene Block (ISB) [2], 019 Citation: Sonawane K, Dixit H, Balavenkatasubramanian J, Gurumoorthi P (2021) Uncovering secrets of the beauty bone: A comprehensive review of anatomy and regional anesthesia techniques of clavicle surgeries. Open J Orthop Rheumatol 6(1): 019-029. DOI: https://dx.doi.org/10.17352/ojor.000034 https://www.peertechzpublications.com/journals/open-journal-of-orthopedics-and-rheumatology combined ISB with superficial cervical plexus block [3], cervical number, having two primary ossification centers, two borders, plexus block [4], a combination of supraclavicular nerve and two curvatures, two ends, two surfaces, and two articulations/ upper (superior) trunk (SCUT) block [5], a combination of a joints. (Figure 1A). pectoral nerve (PEC) I block with selective supraclavicular • Two primary ossification centers: The clavicle is the nerve block [6], modified PEC II block [7] and Clavipectoral first bone to begin the ossification process during the Fascial Plane Block [8-11] (CPB). We present a comprehensive development of the embryo (5th-6th weeks of gestation) review of the clavicle anatomy, its innervation, and different and one of the last bones to finish ossification (21-25 RA techniques used for clavicle surgeries. years of age). Knowledge of functional anatomy and the surgical • Two borders: The anterior and the posterior borders procedure helps in planning the procedure-specific RA give origin to the deltoid muscle and insertion to the technique for the patient. There is a paucity of literature on trapezius muscle in the lateral 1/3rd, respectively. the innervations, associated pathologies, and optimal RA techniques for clavicle fractures. This review will help readers • Two curvatures: The anterior curvature in the medial understand the clavicle anatomy and nature of fractures and 2/3rd and the posterior curvature in the lateral 1/3rd of apply an algorithmic approach to procedure-specific blocks for the clavicle. complexly innervated structures like clavicle. • Two ends: The lateral acromial end is broad, flat, and Functional anatomy of clavicle formed by intramembranous ossification. The medial sternal end is round, pyramidal-like, and formed The clavicle, or collarbone, is also referred to as “beauty by endochondral ossification. bone” because of its prominent body location. It is the only long bone that lies horizontally in the body. The shape of the • Two surfaces: clavicle appears elongated ‘S’ due to its unique anterior and posterior curvatures. It can appear long and slender, thick and 1. Superior surface: It has a smooth appearance bearing short, or any combination due to its complex shape. It consists the acromial facet at the acromial end to form an of spongy cancellous bone within the compact bone shell, acromioclavicular joint. The superior surface of the forming a periosteal collar. It is the only membranous bone medial 2/3rd of the clavicle gives origin to the clavicular outside the skull and is uniquely pierced through-and-through head of the sternocleidomastoid. It is covered by by the Supraclavicular Nerve (SCN) [12]. Thus, it is also referred platysma muscle under which the supraclavicular nerves to as dermal bone. It follows the “rule of two,” i.e., two in lie, providing sensory innervation to the overlying skin. Figure 1: Functional anatomy of the clavicle, classification of clavicle fracture and fascias related to the clavicle A: Various borders, surfaces, ends, processes, and bony landmarks of the clavicle B: Classification of the clavicular fractures C: Various fascias related to the clavicle 020 Citation: Sonawane K, Dixit H, Balavenkatasubramanian J, Gurumoorthi P (2021) Uncovering secrets of the beauty bone: A comprehensive review of anatomy and regional anesthesia techniques of clavicle surgeries. Open J Orthop Rheumatol 6(1): 019-029. DOI: https://dx.doi.org/10.17352/ojor.000034 https://www.peertechzpublications.com/journals/open-journal-of-orthopedics-and-rheumatology 2. Inferior surface: It is rough, with many prominent • Acts as a strut: The clavicle helps to position the arm lines formed due to muscles and ligamentous away from the trunk by providing a stable strut between attachment. It has three bony landmarks: the sternal the arm and the axial skeleton. It allows the muscles facet forming the sternoclavicular joint, the costal to generate adequate power to perform reaching and tuberosity for the costoclavicular, and the conoid elevation tasks. tubercle for conoid ligaments attachments. • Scapular rotation: Out of the total 60° rotation of the • Two Articulations/Joints: It is also called a ‘double plane scapula during the abduction of the arm, 30° comes joint’ as a layer of articular cartilage separates two joint purely from the lateral clavicle, and the remaining 30° cavities. comes from angulation of the whole clavicle and scapula together at the sternoclavicular joint. 1. Acromioclavicular (AC) joint is a plane synovial Fascias related to the clavicle (Figure 1C) joint formed by the acromial end of the clavicle and the acromion of the scapula, connected by Deltoid fascia: It is a fibrous membrane over the outer aspect the acromioclavicular ligament. It supports the function of the deltoid muscle. Superiorly, it is attached to the clavicle, of muscles that move the clavicle. acromion, and the crest of the scapular spine. Inferiorly, it is continuous with the brachial fascia of the arm. Posteriorly, it is 2. Sternoclavicular joint is a saddle-type synovial continuous with the posterior infraspinatus fascia. Anteriorly, it joint formed by the sternal end of the clavicle and unifies with the pectoral fascia at its frontal-most edge. the manubrium sterni, joined by sternoclavicular ligaments, anterior and posterior interclavicular Pectoral fascia: It is a thin layer of fascia covering the ligaments. The anterior interclavicular ligament prevents pectoralis major muscle. It is attached medially to the sternum clavicle dislocation upon shoulder depression, whereas superiorly to the clavicle, and inferolaterally, it is continuous the posterior interclavicular (costoclavicular) ligament with the fascia of the thorax, shoulder, and axilla. At its most lateral section, it forms the floor of the axilla as the axillary prevents